Resonance Wavelength Stabilization of Quasi-Bound States in the Continuum Constructed by Symmetry Breaking and Area Compensation
Shaojun You, Haoxuan He, Ying Zhang, Hong Duan, Lulu Wang, Yiyuan Wang, Shengyun Luo, Chaobiao Zhou
Abstract
Dielectric metasurface supported symmetry-protected bound states in the continuum (SP-BIC) provide an important platform for enhancing light–matter interactions. However, the conversion of SP-BIC into quasi-BIC (QBICs) through symmetry breaking is often accompanied by a shift in the resonance wavelength. In this work, we present a generalized viewpoint aimed at achieving the wavelength stability of QBICs through symmetry breaking and area compensation (SBAC). Three SBAC schemes we propose are equal proportional compensation along both x - and y -directions and equal proportional compensation along x -direction only or y -direction only. The QBICs resonance wavelengths stabilized at about 1200, 1520, and 1434 nm are achieved in monomer, dimer, and tetramer metasurfaces, respectively. Finally, we perform an experimental demonstration in a nanohole dimer photonic crystal slab. The QBICs resonance wavelength stabilized at 1658 nm for SBAC. Our approach provides new routes for realizing QBICs with a stable wavelength and tunable Q-factor.